Printing cylinder assembly



April 1968 L. SCHOLLENBERGER 3376,14

PRINTING CYLINDER ASSEMBLY Filed Feb. 28, 1967 4 Sheets-Sheet 1 FEW April 1968 L. SCHOLLENBERGER 3,376,814

PRINTING CYLINDER AS SEMBLY Filed Feb. 28. 1967 4 Sheets-Sheet 2 April 9, 1968 SCHOLLENBERGER 3,376,814

PRINTING CYLINDER ASSEMBLY 4 Sheets-Sheet 3 Filed Feb. 28, 1967 FI"G.3

April 9, 1968 L. SCHOLLENBERGER 3,375,314

PRINTING CYLINDER ASSEMBLY Filed Feb. 28, 1967 4 Sheets-Sheet 4 a; U EDQ iiiiiiiiiiiiiii.....'.'ll

F|G.7 FIG.8

United States Patent 3,376,814 PRINTING CYLINDER ASSEMBLY Ludwig Schollenberger, Leirnen, near Heidelberg, Germany, assignor to Schnellpressenfabrik Aktiengesellschaft Heidelberg, Heidelberg, Germany, a corporation of Germany Filed Feb. 28, 1967, Ser. No. 619,390 Claims priority, application Germany, Mar. 2, 1966, Sch 38,579/66 6 Claims. (Cl. 101-384) ABSTRACT OF THE DISCLOSURE Printing cylinder assembly includes a printing plate cylinder having a printing-plate engaging surface interrupted by a channel extending in the axial direction of the cylinder and a curved printing printing plate such as a clich, electroplate or the like superimposed on the plateengaging surface, the curved printing plate having undercut recesses formed on the underside thereof for receiving support facets therein. Arcuate members are displaceably received in grooves of equal width extending respectively about the periphery of the printing-plate engaging surface and disposed alongside one another in the axial direction of the cylinder, the grooves having ends opening into the channel. The arcuate members are formed with a plurality of bores extending from the outer convex surface thereof in a direction inclined to the direction in which a clamping force is to be applied thereto, the bores being adapted to hold support facets receivable in the undercut recesses of the curved printing plate mounted on the plate-engaging surface. A rack of inclined teeth is formed at least at one end of the arcuate members on the concave side thereof facing the printing plate cylinder. A self-locking worm is turnably mounted on a wall of the channel beneath one of the open groove ends and meshes laterally in the teeth of the arcuate members so as to clamp the arcuate members to the printingplate engaging surface and thereby the curved printing plate is secured to the arcuate members by the support facets received in the undercut recesses formed in the underside of the curved printing plate.

My invention relates to printing cylinder assembly and more particularly to such an assembly wherein a curved printing plate such as a clich, electroplate or the like is clamped to a printing plate cylinder having a printingplate engaging surface interrupted by a channel extending in the axial direction of the cylinder, the curved printing plate having undercut recesses formed on the underside thereof for receiving support facets therein.

Clamping devices for curved printing plates are known wherein arcuate members carrying facets are guided displaceably in grooves extending in the peripheral direction of a circular cylinder. These arcuate members have teeth on the undersurface thereof which mesh with a gear carried in the cylinder. The gear is in turn mounted on a shaft extending longitudinally through the entire cylinder and is actuable at the cylinder end wall by an endless worm or screw. Several of such gears are simultaneously located on one shaft so that by actuating the shaft, a series of arcuate members carrying facets are displaced at the same time in the peripheral direction.

The stationary arrangement of the arcuate members,

in addition to the high cost thereof, are disadvantages V in the aforementioned known clamping device. Curved printing plates or clichs of a predetermined size only are able to be used. Furthermore, it is disadvantageous for the arcuate members to be adjustable in groups.

In another known clamping device for curved clichs facet-carrying arcuate members are similarly displaceable in the peripheral direction of the supporting cylinder. In this known device, teeth located at the underside of each arcuate member cooperate with a gear, the same as in the aforementioned known device. The arcuate members of this known device are self-adjustable, however, because they are respectively provided with an adjusting worm or screw, formed with a bore in which a key is insertable for turning the worm, the bore being in the surface of the cylinder casing. A disadvantage of this known device is that, due to the respectively fixed locations of the support facets, the side of the curved clichs and electroplates or the like must be predetermined beforehand. This type of clamping is of advantage only for rotary presses wherein the curved clich-s that are used have the same size and arrangement.

It is accordingly an object of my invention to provide printing cylinder assembly and the means for clamping the same together which avoid the disadvantages of the heretofore known devices and, more particularly, are able to clamp curved printing plates or clichs of varying size individually on a printing plate cylinder at any desired location thereof by means of support facets.

With the foregoing and other objects in view, I provide, in accordance with my invention, printing cylinder assembly wherein the printing-plate engaging surface of the printing plate cylinder is formed with peripheral grooves located along the longitudinal axis of the cylinder, the grooves being substantially of the same width and having ends opening into a longitudinally extending channel interrupting the printing-plate engaging surface. Displaceable arcuate members are insertable in the grooves so that they preferably fill the entire cross section thereof, the upper convex surface of the arcuate members being provided with bores extending therethrough in a direction inclined with respect to the direction of clamping of the arcuate members to the printing plate cylinder and are adapted to receive therein support facets. Furthermore, at least at one end of the arcuate member, in the concave underside thereof facing the plate cylinder, there is formed a rack of teeth in which a self-locking worm, turnably mounted on the wall of the channel beneath one of the open groove ends, meshes laterally so as to clamp the arcuate member to the plate-engaging surface of the cylinder.

By providing a series of grooves of equal width in the cylinder surface wherein arcuate members of varying length can be inserted, it is possible to clamp curved printing plates of varying size easily at any location of the plate-engaging surface of the cylinder to which it is to be clamped. Furthermore, with the assembly of my invention it is of advantage that only so many clamping units are required at any one time .as are necessary for securing the curved printing plates used for the particular operation. The expense required for clamping curved printing plates is thereby much lower than for the heretofore known clamping devices wherein a large number of clamping units are provided even when only a few thereof are actually used. Moreover, with the assembly of my invention which includes a printing plate cylinder having a printing-plate engaging surface interrupted by a channel extending in the axial direction of the cylinder, the printing surface of the curved printing plate which is to be clamped to the plate-engaging surface of the cylinder can be utilized completely up to the very edge of the channel.

An advantageous further feature of my invention is that the worm is provided with a bearing pin turnably connected with a strap or bracket that is provided with a guide opening for receiving and guiding the end of a respective arcuate member having a toothed rack which is insertable therein. A mounting bore is further provided, in accordance with my invention, in the channel wall of the plate cylinder under each open groove end wherein an additional free bearing pin of the Worm can be turnably inserted. It is thereby possible not only to select the number of arcuate members that are required but also the number of necessary adjusting worms. Small curved printing plates or clichs or the like can be clamped with two or oven only with one support facet along each edge thereof while larger printing plates can be clamped with three or four facets at each side thereof.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in printing cylinder assembly, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of a specific embodiment when read in connection with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of substantially half of a printing cylinder assembly constructed in accordance with my invention wherein a curved clich is shown clamped at a starting edge of the plate-engaging surface of a printing plate cylinder;

FIG. 2 is a cross-sectional view of the other half of the assembly shown in FIG. 1;

FIG. 3 is a diagrammatic developed axial view of part of the printing cylinder assembly of my invention and FIG. 4 is a view of FIG. 3 rotated through 90, both views showing inserted front and side facets;

FIG. 5 is a side view of an arcuate member of my invention shown in assembly with one inserted support facet;

FIG. 6 is a top plan view of FIG. 5;

FIGS. 7 and 8 are front and side views respectively of the support facet shown in FIGS. 5 and 6;

FIG. 9 is a longitudinal view of the clamping worm constructed in accordance with the invention;

FIGS. 10 and 11 are side and plan views respectively of the mounting strap or bracket for the worm of FIG. 9; and

FIGS. 12 and 13 are longitudinal and plan views respectively of the assembled worm and mounting bracket.

Referring now to the drawings and first particularly to FIGS. 1 and 2 thereof, there is shown a printing plate cylinder which includes a cylindrical core 1 and easing 2 fitted thereon. The casing 2 does not completely surround the core 1 but is split so as to form a channel 2 extending along the full axial length of the cylinder core 1. Thus, the printing plate cylinder is engageable only over a specific porton of its periphery with curved printing plates such as clichs electroplates or the like, as are employed for example in rotary presses. The curved casing 2 is removable from the core 1 so that the assembly of the printing cylinder proper and the mounting and the type-forming operation of the curved plate can take place on a proof-copy press or the like outside the printing machine.

As shown in FIG. 4, the casing surface is provided with a number of grooves 3 of substantially the same width and depth extending continuously in the peripheral direction thereof and equally spaced from one another along the longitudinal axis of the cylinder. The grooves can be cylindrical or dovetailed in for-m and have open ends at the ends of the cylindrical casing 2 which form the walls 4 of the channel 2.

Arcuate members 5 of varying length are insertable in the grooves 3. The upper convex surface of the arcuate members 5 as shown in FIG. 5 has a series of countersunk inclined bores 6 extending therethrough, while the underside of the arcuate member 5, at one end thereof, is provided with a rack 7 of inclined teeth. Support facets 8 are insertable by means of mounting pins 9 (FIGS. 5 through 8) into the bores 6. The support facets 8 have such a shape that they can come into engagement with undercut recesses or pockets 17 milled or otherwise formed in the curved printing plates or clichs 16, as shown in FIGS. 1, 2 and 4.

Both of the channel walls 4, as aforementioned, are broken by the open-ended grooves 3. Under each of the open groove ends there is provided a bore in the channel wall 4, as shown more clearly in FIG. 3, in which a hearing bushing 10 is press-fitted. The exposed bearing pin 11 of a worm 12 (FIG. 9) can thus be turnably inserted in this bearing bushing 10. The worm 12 is also provided with a second bearing pin 13 which is formed with a hexagonal recess 13 in the head thereof and which is connected turnably with a guide strap or bracket 14 (FIGS. 10 and 11).

The guide bracket 14 has a rectangular guiding hole 15 corresponding to the cross section of the arcuate member 5 which serves to receive therein the end of the arcuate member 5 that is provided with the toothed rack 7, as can be seen for example in FIGS. 1 and 2. The worm 12 and the guide bracket 14 together with the arcuate member 5 provide clamping means for the printing cylinder assembly. The operation of the aforedescribed assembly is as follows:

If a curved printing plate such as a clich 16 is to be clamped so that, as shown in FIGS. 1 and 2, it is to have one of its edges located at the level of the channel wall 4 and clamped at that edge, while the opposite edge of the clich extends slightly over more than half of the periphery of the casing 2 to which it is to be clamped, at short arcuate member 5 is then required to be inserted at the desired location in a groove at the clamping end wall 4 of the casing 2. Below the open end of this groove in the channel wall 4 there is provided a worm 12 with a strap or bracket 14, the bearing pin 11 for the worm 12 being inserted in the bearing bushing 10 provided in a bore formed in the wall 4, and the end of the arcuate member 5 that is provided with the toothed rack is inserted in the guide hole 15 of the strap or bracket 14. As shown in FIG. 1, in the illustrated position thereof, the bore 6 extending through the arcuate member 5 nearest the toothed rack thereof has the pin 9 of a support facet 8 inserted therein, the facet end projecting from the bore 6 engaging in an undercut portion provided in a recess or pocket of a grooved printing plate or clich 16. If the clich 16 is relatively wide, then two or more arcuate members with support facets can be provided for clamping it to arcuate members 5 as shown in FIG. 4, for example.

The other end of the curved printing plate or clich 16 as shown in FIG. 2, is located relatively far from the channel wall 4 in FIG. 2. Consequently, a relatively long arcuate member 5 must here be employed having a facet 8 located in the most distant bore 6 from the toothed end thereof and engaging with an undercut edge in a recess or pocket 17 formed in the undersurface of the curved printing plate or clich 16. As at the clamping end of FIG. 1, there is similarly provided at the other clamping end of the mantle 2 as shown in FIG. 2, a worm 12 having a guide strap or bracket 14 located below the open end of the groove 3, suitably inserted in a bearing bushing which is in turn provided in a bore formed in respective end wall 4 of the channel 2'. The guide bracket 14 as shown in FIG. 2 is also in engagement with the toothed end 7 of the relatively long arcuate member 5 shown in FIG. 2.

The insert connection of the worm is such that by turn ing the worm with a suitable hexagonal tool or key, such as an Allen wrench insertable into the hexagonal hole in the end thereof, the arcuate member 5 can be shifted back and forth along the periphery of the cylinder. After the clamping facets have gripped the undercut edge of the pockets 17 of the curved printing plates or cliches 16 both at the clamping ends shown in FIG. 1 and in FIG. 2 by turning the worm 12, the curved printing plate or clich is then drawn flush against the cylindrical casing 2.

In order additionally to secure the curved printing plate or cliche 16, the cylindrical casing 2 is furthermore provided with several longitudinally extending grooves 18 in which lateral facets 19 are accommodated or installed to hold the printing plate or clich against lateral movement, i.e., movement along the longitudinal axis of the cylinder. The lateral facet 19 is provided with a pin suitably threaded in a bore formed in the casing 2. Each of the support facets accordingly has a clamping worm associated therewith. Consequently, each curved printing plate or clich is accurately able to be adjusted in registry with a specific location therefor, i.e., is able also to be substantially easily clamped by a twisting motion.

I claim:

1. Printing cylinder assembly comprising a printingplate cylinder having a printing plate-engaging surface interrupted by a channel extending in the axial direction of the cylinder, said plate-engaging surface being formed with a plurality of grooves of substantially equal width extending respectively about the peripheral surface 'of' the printing plate-engaging surface and located successively adjacent one another in the axial direction of the cylinder, said grooves having ends opening into said channel, arcuate members displaceably receivable in said grooves and formed with a plurality of bores inclined with respect to a given direction in which a clamping force is applied between said arcuate members and said printingplate cylinder and a rack of inclined teeth formed at least at one end of said arcuate members on the side thereof facing said printing-plate cylinder, a curved printing plate superimposed on said plate-engaging surface and formed, on the side thereof in engagement with said plate-engaging surface, with undercut recesses, support facets adapted to be held in said inclined bores and receivable in said undercut recesses of said curved printing plate, and a self locking worm turnably mounted on a Wall of said channel beneath the open end of each of said grooves wherein an arcuate member is received and meshing laterally in the teeth of the respective arcuate member so as to apply a clamping force in said given direction between said arcuate member and said printing-plate cylinder.

2. Assembly according to claim 1, wherein said arcuate members are of varying length.

3. Assembly according to claim 1, wherein said plurality of inclined bores are serially arranged in said arcuate members, said support facets having a respective pin portion receivable in one of said inclined bores.

4. Assembly according to claim 1, including a bracket having a guide opening for receiving and guiding the toothed end of the respective arcuate member, said worm having a mounting pin turnably connected with said bracket, said wall of said channel beneath the open end of said grooves being formed with a respective bore, and said worm having another exposed mounting pin turnably inserted in said last-mentioned bore.

5. Assembly according to claim 4, wherein said bearing pin connected to said bracket is formed with a polygonal bore for receiving a tool to turn said worm.

6. Clamping device for a printing cylinder assembly comprising a printing-plate cylinder having a printing plate-engaging surface interrupted by a channel extending in the axial direction of the cylinder, said plate-engaging surface being formed with a plurality of grooves of substantially equal width extending respectively about the peripheral surface of the printing plate-engaging surface and located successively adjacent one another in the axial direction of the cylinder, said grooves having ends opening into said channel, arcuate members displaceably receivable in said grooves and formed with a rack of inclined teeth located at least at one end of said arcuate members on the side thereof facing said printing-plate cylinder, and a self-locking worm turnably mounted on a wall of said channel beneath the open end of each of said grooves wherein an arcuate member is received and meshing laterally in the teeth of the respective arcuate member so as to apply a clamping force between said arcuate members and said printing-plate cylinder.

References Cited UNITED STATES PATENTS 2,406,883 9/1946 Luehrs 10l384 2,953,090 9/1960 Scott 101-378 3,000,301 9/1961 Barthel 10l375 FOREIGN PATENTS 619,093 4/1961 Canada.

ROBERT E. PULFREY, Primary Examiner. C. D. CROWDER, Assistant Examiner. 

